Natalie Portman's Dior ad banned

An ad featuring Natalie Portman has been banned for being misleading.Photo / Supplied

An advertisement for a Christian Dior mascara featuring actress Natalie Portman has been banned for exaggerating the effect of the product on her lashes.

The magazine ad showed a picture of the Oscar-winning actress with the text: "Lash-multiplying effect volume and care mascara. The miracle of a nano brush for an unrivalled lash creator effect. It delivers spectacular volume-multiplying effect, lash by lash."

The UK's Advertising Standards Authority (ASA) investigated the ad after L'Oreal complained that it misleadingly exaggerated the likely effects of the product.

Defending the campaign, Dior said it had not received any complaints from consumers and believed this meant that the ad did not exceed likely expectations of the mascara.

But it said Portman's natural lashes were digitally retouched in post-production using Photoshop software, explaining that the retouching was "nearly exclusively in relation to her upper lashes and was primarily used to separate/increase the length and curve of a number of her lashes and to replace/fill a number of missing or damaged lashes".

A "minimal amount" of retouching also took place to increase the thickness and volume of a number of her natural lashes.

The ASA said Dior provided some before and after photos showing a model's natural eyelashes and the effects of the product on her lashes, but it had not seen evidence of the mascara's effects on Portman's lashes where there had not been any post-production retouching.

"We were concerned that we had not seen evidence that the visual representation of the product's effects on Natalie Portman's lashes, as featured in the ad, could be achieved through use of the product only, particularly as we understood that post-production retouching on the lash area had taken place.

"Because we considered that we had not seen sufficient evidence to show that the post-production retouching on Natalie Portman's lashes in the ad did not exaggerate the likely effects of the product, we concluded the ad was likely to mislead," the ASA said.